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Sedna

90377 Sedna is a large trans-Neptunian object and dwarf planet candidate located in the outermost reaches of the Solar System, notable for its extreme orbital eccentricity and distance from the Sun.^[1] Discovered on November 14, 2003, by astronomers Michael E. Brown of the California Institute of Technology, Chadwick A. Trujillo of the Gemini Observatory, and David L. Rabinowitz of Yale University using the Samuel Oschin 48-inch Samuel Oschin Telescope at Palomar Observatory in California, Sedna was the most distant Solar System object observed at the time of its discovery, at about 89 AU from the Sun.^[2]^[1] The object is named after Sedna, the Inuit goddess of the sea and marine animals, reflecting its cold, icy nature.^[2] Sedna orbits the Sun in a highly elliptical path with a semi-major axis of approximately 552 AU, an eccentricity of 0.862, and an inclination of 11.9° relative to the ecliptic, resulting in a perihelion distance of about 76 AU—beyond the Kuiper Belt—and an aphelion of approximately 1,028 AU, placing it in the inner Oort Cloud.^[3] Its orbital period is estimated at around 13,000 years, making it the longest-period object of its size known in the Solar System.^[3] As of 2025, Sedna is approximately 83 AU from the Sun, approaching its perihelion, expected around 2076, which will bring it closer to the inner Solar System than at any time in the last 12,000 years.^[2]^[4] Physically, Sedna has an estimated diameter of 995 km, based on thermal measurements from space telescopes like Spitzer and WISE, assuming a high geometric albedo of 0.32, which classifies it among the largest known trans-Neptunian objects after the recognized dwarf planets.^[5] Its surface exhibits a bright red color in visible and near-infrared spectra, attributed to a mixture of water, methane, and nitrogen ices processed into complex organic compounds called tholins by cosmic ray irradiation over billions of years.^[6] Recent spectroscopic observations have detected additional volatile ices such as ethane, acetylene, and ethylene on its surface, indicating a pristine, heterogeneous composition little altered since formation.^[7] Sedna's unusual orbit, detached from Neptune's influence and shared by a small population of similar "sednoids," challenges models of Solar System formation and suggests possible dynamical interactions with a hypothetical Planet Nine or capture from another star system during the Sun's early passage through a stellar cluster.^[2] Although not officially designated a dwarf planet by the International Astronomical Union due to limited observations confirming hydrostatic equilibrium, its size and likely spherical shape make it a strong candidate, and it remains a prime target for future missions to explore the distant Oort Cloud.^[1]

Discovery and naming

Discovery

Sedna was discovered on November 14, 2003, by astronomers Michael E. Brown of the California Institute of Technology, Chadwick A. Trujillo of the Gemini Observatory, and David L. Rabinowitz of Yale University, during a wide-area survey for bright Kuiper Belt objects using the Samuel Oschin 48-inch telescope at Palomar Observatory equipped with the Palomar-QUEST camera.^[8] The object was identified as a slow-moving point source with an apparent magnitude of R = 20.7, moving at 4.6 arcseconds over 3.1 hours, at a heliocentric distance of approximately 90.3 AU from the Sun.^[8]^[9] Follow-up observations confirmed the detection on November 18, 2003, with additional imaging on November 21 and 24 using the Samuel Oschin telescope, as well as observations from the Tenagra IV observatory, Keck Observatory, and the 1.3-meter SMARTS telescope at Cerro Tololo Inter-American Observatory through December 31, 2003.^[8] Precovery identifications extended the observational arc, with images recovered from the NEAT survey on September 26 and October 24, 2001; October 9 and 29, 2002; and August 30 and September 29, 2003, using the Samuel Oschin telescope and Palomar QUEST camera, further refining the preliminary orbit.^[8] Later archival searches identified additional precovery images in the Palomar Digitized Sky Survey dating back to September 25, 1990.^[8] The discovery received the provisional designation 2003 VB<sub>12</sub> from the Minor Planet Center.^[8] It was publicly announced on March 15, 2004, through a joint press release from Caltech, Yale University, and the Gemini Observatory, prior to formal numbering by the International Astronomical Union (IAU), which sparked minor controversy over the informal use of the name "Sedna" before official procedures were completed.^[10]^[9] At the time, Sedna was the most distant observed object in the Solar System, establishing it as a significant find in the outer reaches beyond the Kuiper Belt.^[8]

Naming

The name Sedna derives from the Inuit goddess of the sea and marine animals, who is said to control ocean life and was chosen by the discovery team to evoke the object's extreme cold and remoteness in the outer Solar System, as well as its relative ease of pronunciation across languages.^[9]^[11] The proposal was made by co-discoverer Michael E. Brown in March 2004, drawing specifically from Arctic mythology to reflect the frigid conditions anticipated for such a distant body.^[9]^[11] The International Astronomical Union's Committee on Small Body Nomenclature officially accepted the name on September 28, 2004, assigning the permanent designation 90377 Sedna to the object previously known provisionally as 2003 VB12.^[12] Sedna's astronomical symbol is Unicode U+2BF2 (⯲), an arrow-like glyph designed to represent a seal emerging from water, derived from Inuktitut syllabics for "Sanna" (the modern form of the goddess's name); it is primarily employed in astrological contexts rather than standard astronomical notation.^[13] The naming process sparked debate when the discovery team announced "Sedna" publicly in March 2004, prior to the object's official IAU numbering in September 2004, which contravened then-existing protocols requiring names to be withheld until after numbering.^[12]^[11] This procedural violation drew criticism from figures like IAU naming board secretary Brian Marsden, who noted it could influence committee votes, though no objections arose to the name itself.^[11] The issue was resolved without altering the designation, prompting the Committee on Small Body Nomenclature to revise guidelines in 2006 to permit pre-numbering proposals for exceptionally significant objects with secure orbits, provided they are submitted in advance and not publicized prematurely.^[14]

Orbit

Orbital parameters

Sedna possesses one of the most extreme orbits known in the Solar System, characterized by a high eccentricity and a semi-major axis far beyond the Kuiper Belt. Its orbital period is approximately 11,400 years in the barycentric reference frame, reflecting the immense scale of its path around the Sun. The key orbital elements, based on osculating values at epoch JD 2460000.5 (2023-Feb-25), include a semi-major axis of 506.8 AU, an eccentricity of 0.8496, a perihelion distance of 76.19 AU, and an aphelion of 937 AU. The orbit is inclined by 11.9307° relative to the ecliptic plane, with a longitude of the ascending node at 144.5° and an argument of perihelion at 311.5°. These parameters define a highly elongated trajectory that spends most of its time in the distant outer Solar System.^[15] As of November 2025, Sedna is approximately 83.2 AU from the Sun and continues its inward journey toward perihelion, the closest point to the Sun in its orbit. The next perihelion passage is projected for around July 18, 2076, at a distance of 76.43 AU—marking the innermost approach since its discovery in 2003 and offering a rare observational window before it recedes once more. Dynamically, Sedna's orbit is detached, lying well beyond the gravitational influence of Neptune at 30 AU, with no significant mean-motion resonances involving the giant planets. This isolation underscores its classification as an inner Oort cloud object, minimally perturbed by planetary perturbations over its long orbital cycle.^[16]

Rotation

Sedna's sidereal rotation period is 10.273 ± 0.002 hours, determined through analysis of its photometric light curve obtained using ground-based observations with the 6.5 m MMT telescope equipped with the MegaCam instrument in 2004 and 2005.^[17] These data, consisting of 143 precise r-band measurements with ~1% photometric precision, revealed a sinusoidal variation that best fits this period, ruling out shorter rotations below ~5 hours or longer ones exceeding ~10 days at greater than 3σ confidence.^[17] An alternative period of approximately 18 hours provides a marginally acceptable fit but is considered less likely due to poorer alignment with the data.^[17] The light curve displays a low semi-amplitude of 1.1 ± 0.1% (equivalent to ~0.04 magnitudes), indicating minimal variation in reflected sunlight as Sedna rotates.^[17] This subdued amplitude, combined with Sedna's estimated size of over 900 km, suggests a nearly spherical shape rather than significant elongation, with any observed variability more likely attributable to heterogeneous surface albedo than geometric effects.^[18] Observations with the Hubble Space Telescope in 2004 further supported these findings by confirming the absence of a massive companion, which had been hypothesized to explain an initially inferred slower rotation through tidal interactions; the confirmed period aligns with typical spin rates for large trans-Neptunian objects.^[19] The orientation of Sedna's rotation axis remains poorly constrained due to limited multi-epoch observations, preventing determination of its obliquity relative to the orbital plane.^[17] The low light curve amplitude is consistent with either a highly uniform surface or a nearly pole-on viewing geometry, but insufficient data preclude distinguishing these scenarios or quantifying any axial tilt. This rotational profile, with its moderate period and near-spherical implications, bolsters evidence for Sedna maintaining hydrostatic equilibrium under self-gravity, a key criterion for its consideration as a dwarf planet candidate.^[18]

Physical characteristics

Size and shape

Sedna's diameter has been estimated using thermal infrared observations and stellar occultations. Measurements from the Herschel Space Observatory in 2012 provided a diameter of 995 ± 80 km, based on its thermal emission.^[20] A stellar occultation observed in 2013 yielded a chord length of 1025 ± 135 km, establishing a lower limit on the diameter greater than this value.^[21] The geometric albedo of Sedna is 0.32 ± 0.06 in the V-band, derived from the same Herschel observations, which is relatively high and suggests a surface dominated by reflective ices.^[20] Earlier photometric models assuming a higher albedo of approximately 0.41 yielded a smaller diameter estimate of about 906 km when combined with Sedna's absolute magnitude of H = 1.8. Sedna's mass and density cannot be directly measured due to the absence of known satellites or spacecraft flybys. Assuming a typical density of 2.0 g/cm³ for trans-Neptunian icy bodies and the Herschel-derived diameter, the mass is estimated at approximately 1.0 × 10^{21} kg. Recent models based on JWST observations of volatile retention suggest a minimum mass sufficient to retain ethane but not methane, aligning with or raising the lower bound of previous estimates (as of 2025).^[20]^[22] Sedna is modeled as an oblate spheroid, consistent with rotational flattening for objects of its size. Photometric light curve observations reveal no significant irregularities, with a variation amplitude less than 0.2 magnitudes, indicating a shape close to spherical.^[23]

Surface composition

Sedna exhibits an extremely red color in visible light, with a spectral slope that makes it one of the reddest known objects in the Solar System, second only to Mars. This coloration is attributed to the presence of tholins—complex organic polymers formed from the irradiation of simpler hydrocarbons—covering much of its surface, as inferred from early spectroscopic analyses.^[24] These tholins contribute to a steep red slope in the visible spectrum, distinguishing Sedna from typical Kuiper Belt objects, which are generally less red. The surface composition of Sedna is dominated by water ice, with detections of various irradiated hydrocarbons and possible minor volatiles. Observations from the James Webb Space Telescope (JWST) in 2023 using the NIRSpec instrument revealed prominent absorptions from ethane (C₂H₆), ethylene (C₂H₄), and acetylene (C₂H₂), indicating active irradiation chemistry processing underlying ices.^[25] Earlier ground-based near-infrared spectroscopy confirmed water ice as the primary component, with upper limits suggesting low abundances of methane (CH₄ < 60%) and nitrogen (N₂ < 30%), and possible traces of carbon dioxide (CO₂).^[18] No substantial atmosphere has been detected, consistent with Sedna's low gravity and cold temperatures, which prevent significant volatile retention.^[25] Spectral features include broad absorption bands between 2.7–3.6 μm attributed to complex organic molecules and irradiated water ice, alongside narrower features from light hydrocarbons across 0.7–5.2 μm.^[25] At its current heliocentric distance of approximately 83 AU, Sedna's equilibrium surface temperature is around 30 K, calculated assuming a moderate albedo and blackbody equilibrium.^[25] Over millennia, the surface has likely been heavily altered by cosmic ray bombardment and solar wind particles, driving the formation of tholins and hydrocarbons from primordial ices without significant resurfacing events.^[24]

Classification and origin

Classification

Sedna is classified as a trans-Neptunian object (TNO), a broad category encompassing all minor planets orbiting the Sun beyond Neptune's orbit. More specifically, it belongs to the sednoid population, defined by a perihelion distance greater than 72 AU and a semi-major axis exceeding 150 AU, placing it in a dynamically detached region far from Neptune's gravitational influence. This classification stems from its extreme orbital parameters, which isolate it from typical Kuiper Belt interactions. Sedna is also regarded as an extended scattered disc object, characterized by high-eccentricity orbits with perihelia beyond 30 AU, though its detachment suggests minimal ongoing scattering by giant planets. Regarding its planetary status, Sedna is a strong candidate for dwarf planet designation under International Astronomical Union (IAU) criteria, which require a body to orbit the Sun, be nearly spherical due to hydrostatic equilibrium, and not have cleared its orbital neighborhood. Its estimated diameter of approximately 995 km and predominantly icy composition—dominated by water ice with traces of methane and nitrogen—indicate it is likely in hydrostatic equilibrium, achieving a rounded shape under self-gravity. However, Sedna has not cleared its neighborhood, as evidenced by a Stern-Levison parameter much less than 1, reflecting its low mass relative to the dynamical dominance needed for full orbital clearing. The IAU has not officially recognized Sedna as a dwarf planet as of 2025, with only Ceres, Pluto, Haumea, Makemake, and Eris formally classified in this category; Sedna's status awaits further dynamical analysis and shape confirmation.^[26] In comparison to Pluto, another IAU-recognized dwarf planet, Sedna exhibits similarities in composition, with both featuring volatile ices like methane and nitrogen on their surfaces, suggesting formation in comparable outer Solar System conditions. However, Sedna's orbit is markedly more distant, with a semi-major axis about 14 times that of Pluto's, emphasizing its extreme isolation.

Origin hypotheses

The extreme orbit of Sedna, characterized by a high eccentricity and a perihelion well beyond the influence of Neptune, has prompted several hypotheses regarding its dynamical origin, primarily focusing on events in the early Solar System. One leading scenario posits that Sedna was perturbed by a close encounter with a passing star during the Sun's birth in a dense stellar cluster approximately 4.5 billion years ago. In this model, the gravitational tug from a nearby star, estimated to have approached within about 800 AU, could have excited Sedna's eccentricity while preserving its high perihelion, implanting it into an inner Oort cloud orbit without significant disruption to the outer planets.^[27] This hypothesis aligns with N-body simulations of the young Solar System embedded in such clusters, which demonstrate that stellar flybys at distances of 100–500 AU can efficiently produce Sedna-like orbits for a subset of scattered planetesimals.^[28] Another proposed mechanism involves the influence of a hypothetical massive planet, often referred to as Planet Nine, which could have scattered Sedna inward from the outer Oort cloud. Numerical models indicate that a distant, eccentric planet with a mass of 5–10 Earth masses orbiting at 400–800 AU would naturally shepherd extreme trans-Neptunian objects like Sedna into clustered, high-perihelion orbits through repeated gravitational resonances and scatterings. A less favored idea suggests Sedna was captured from the protoplanetary disk of a passing star during the Sun's early migration through the galaxy. While N-body simulations show that such captures are possible during close stellar encounters (within ~340 AU of a 1.8 solar mass star), the required relative velocities and orbital alignments make this scenario improbable, as captured objects typically exhibit mismatched inclinations or excessive velocities relative to the Sun. Sedna's orbit is often interpreted as evidence for membership in a populated inner Oort cloud, a region extending from roughly 50 to 300 AU where planetesimals were dynamically excited but not fully ejected during the Solar System's formation. This inner shell, distinct from the classical Oort cloud, likely formed through the combined effects of giant planet scattering and early stellar perturbations, with Sedna representing a surviving prototype that implies a broader population of similar objects.

Sednoid population

Known sednoids

The first confirmed sednoid after Sedna is 2012 VP113, nicknamed "Biden," discovered on November 5, 2012, by astronomers Chad A. Trujillo and Scott S. Sheppard using the Dark Energy Camera on the Blanco 4-m telescope at Cerro Tololo Inter-American Observatory in Chile.^[29] This object has a perihelion distance of 80 AU and a semi-major axis of 262 AU, placing it on a highly eccentric orbit (e ≈ 0.69) that remains detached from Neptune's gravitational influence.^[29] Its estimated diameter is around 450 km, and it exhibits a red surface color typical of outer Solar System bodies.^[30] In 2018, Sheppard, Trujillo, and colleagues announced the discovery of 2015 TG387, later officially named (541132) Leleākūhonua, also observed with the Dark Energy Camera as part of a search for distant Solar System objects.^[30] This sednoid has a perihelion of 65 AU and an exceptionally large semi-major axis of 1170 AU, resulting in an eccentricity of about 0.94 and an orbital inclination of 12° relative to the ecliptic.^[30] With an estimated size of 300 km and a reddish hue, it orbits the Sun once every 40,000 years, spending most of its time far beyond the Kuiper Belt.^[30] In July 2025, astronomers announced the discovery of 2023 KQ14, nicknamed "Ammonite," observed in 2023 using the Subaru Telescope in Hawaii as part of the FOSSIL survey by a team led by Ying-Tung Chen from Academia Sinica.^[31] This sednoid has a perihelion of 66 AU, a semi-major axis of 252 AU, an eccentricity of approximately 0.74, and an inclination of 11° relative to the ecliptic.^[31] Its estimated diameter is 220–380 km, and it has an orbital period of about 4000 years.^[31] Like other sednoids, it exhibits a reddish color indicative of primitive organic-rich surfaces. The known sednoids, including these examples, were primarily uncovered by dedicated surveys such as the Dark Energy Survey (DES) and the Outer Solar System Origins Survey (OSSOS), which scanned wide sky areas for faint, distant targets using large ground-based telescopes.^[30] They commonly display high eccentricities ranging from 0.7 to 0.9, red optical colors suggesting primitive surfaces rich in organic materials, and diameters between 200 and 600 km, reflecting their likely formation in the early, outer Solar System.^[30]

Estimated population

Estimates of the sednoid population, which includes objects with perihelia greater than 50 AU and semi-major axes beyond 150 AU, suggest a sparse but significant reservoir in the inner Oort cloud. Early modeling based on the discovery survey for Sedna indicated that 40–120 objects comparable in size to Sedna (diameter approximately 900 km) likely exist with similar extreme orbits. More recent analyses, incorporating data from wide-field surveys, refine this to around 20 such large sednoids (diameter >1000 km), with hundreds of intermediate-sized objects (200–500 km diameter) and thousands smaller than 100 km, reflecting an extrapolated power-law size distribution akin to that of the hot trans-Neptunian objects.^[32] The total mass of the sednoid population for objects larger than 40 km is estimated at approximately 1 × 10^{22} kg, roughly equivalent to the mass of Pluto and several times that of the asteroid belt, comparable to the outer regions of the Kuiper Belt. This estimate assumes a cumulative size distribution with a slope of q ≈ 5, derived from observational simulations that account for detection efficiencies in existing surveys. For objects larger than 100 km, the population may number around 2 × 10^5, implying a substantial contribution to the dynamical structure of the distant Solar System.^[32] Current detection biases in surveys favor brighter, closer objects with lower inclinations, as most observations are optimized for ecliptic-plane searches and limited by magnitude thresholds (e.g., r < 24). Deeper, unbiased searches reveal a paucity of sednoids with perihelia between 50 and 75 AU, suggesting the population density increases at greater distances. The inner Oort cloud (semi-major axes 2000–20,000 AU) may harbor 10^4 to 10^5 additional sednoids, primarily small bodies, though these remain undetected due to their faintness and slow apparent motion.^[33] Population models rely on data from the Outer Solar System Origins Survey (OSSOS) and the Dark Energy Survey (DES), which have characterized detached trans-Neptunian objects but found few extreme sednoids, assuming a steady-state distribution shaped by ancient perturbations rather than ongoing scattering. These models incorporate implantation efficiencies from N-body simulations of stellar encounters or planetary influences, predicting a low-inclination bias intrinsic to the population's formation.^[33]^[34]^[32] Such a population could explain the observed clustering in the Oort cloud's inner structure and provides constraints on hypothetical massive perturbers, requiring a Planet Nine-like object with mass greater than 5 Earth masses to shepherd or implant these orbits without overproducing high-inclination objects. This inferred mass and distribution align with dynamical stability analyses, highlighting sednoids as probes of early Solar System evolution.^[32]

Observations and exploration

Telescopic observations

Following its discovery, Sedna was targeted by the Hubble Space Telescope in April 2004 for high-precision astrometric measurements and initial characterization of its rotational properties. The observations, spanning 35 exposures over five days, provided accurate positional data to support early orbital determinations and revealed no evidence of a satellite, contrary to expectations based on ground-based light curves suggesting a slow rotation period exceeding 20 days. In 2005, the Spitzer Space Telescope conducted thermal infrared photometry of Sedna at wavelengths of 24 and 70 microns to constrain its size. These observations detected faint thermal emission, yielding an upper limit on the diameter of approximately 1,670 km and informing early estimates of its geometric albedo around 0.2, though with significant uncertainties due to the object's distance and low signal-to-noise ratio. Mid-infrared observations with the Herschel Space Observatory in 2010–2011, analyzed in 2012, refined Sedna's physical parameters through multi-wavelength thermal modeling. The data at 70, 100, and 160 microns produced a diameter estimate of 995 ± 80 km and a geometric albedo of 0.32 ± 0.06, highlighting Sedna's relatively bright surface compared to other trans-Neptunian objects.^[20] More recent spectroscopic efforts include James Webb Space Telescope (JWST) observations using the Near-Infrared Spectrograph (NIRSpec) in 2023, which captured prism-mode spectra from 0.6 to 5.3 microns and detected signatures of ethane ice along with other volatile hydrocarbons. Analysis of Hubble data in 2005 refined Sedna's rotation period to 10.27 hours, typical for objects of its size and not requiring a satellite for explanation.^[25]^[17] Ongoing monitoring primarily involves annual astrometric observations from ground-based telescopes to refine Sedna's orbit, with positions reported to the Minor Planet Center accumulating over two decades. No major dedicated observational campaigns have occurred since the JWST spectroscopy due to Sedna's increasing faintness, reaching a visual magnitude of approximately 21.5 in 2025. Sedna's extreme distance poses significant observational challenges, including its faint apparent brightness and exceedingly slow angular motion across the sky, which restrict the feasibility of high-resolution imaging and limit the total observational arc to about 22 years as of 2025. These factors necessitate long integration times and precise tracking, often resulting in sparse data sets that complicate detailed dynamical and physical modeling.^[31]

Proposed missions

Sedna's perihelion passage on 9 March 2076 (JPL 2020 epoch), when it will reach its closest approach to the Sun at 76 AU, presents a rare opportunity for spacecraft missions by significantly reducing the required delta-v for intercept compared to its current distance of over 80 AU.^[35] This alignment allows for more efficient trajectories, enabling flyby encounters that would otherwise demand excessive propulsion capabilities. Mission concepts typically involve gravity assists from Jupiter to optimize launch windows, with favorable opportunities identified for departures in 2029 or 2034 (as of 2022 analyses), leading to one-way trip durations of approximately 24.5 years and arrivals around 2053-2058.^[37] These trajectories would position the spacecraft near Sedna at distances near 76-77 AU from the Sun, allowing close flybys before or shortly after perihelion.^[38] Proposed spacecraft designs draw from New Horizons-like architectures, emphasizing compact, nuclear-powered probes capable of flyby operations for high-resolution imaging, spectroscopy to analyze surface composition, and instruments to sample the surrounding dust and plasma environment.^[39] Advanced propulsion systems, such as nuclear thermal or direct fusion drives, are under consideration to shorten travel times to under 10 years in some feasibility studies (as of 2025), though these remain experimental.^[40] The primary scientific objectives include in-situ measurements of Sedna's surface properties, such as its icy volatiles and potential geological features, to refine models of inner Oort Cloud formation and dynamics.^[39] Additional goals encompass characterizing the plasma environment and any faint magnetic interactions, providing direct data to test hypotheses about distant solar system object evolution.^[41] Key challenges include the extreme distance, necessitating reliable nuclear power sources for long-duration operations, and the overall mission complexity, with estimated costs exceeding $2 billion due to propulsion development and extended flight times.^[42] As of 2025, no missions to Sedna have been approved by NASA, ESA, or other agencies, though conceptual studies continue to advocate for prioritization ahead of the 2076 window.^[37]

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[33]
Discovery and dynamics of a Sedna-like object with a perihelion of ...
Jul 14, 2025 · Here we report the discovery of a Sedna-like TNO, 2023 KQ 14 , nicknamed 'Ammonite', with q = 66 au, a = 252 au and inclination i = 11°.Missing: NASA | Show results with:NASA
[34]
2029 will be the perfect year to launch a mission to Sedna - Phys.org
Jan 5, 2022 · There are no missions to Sedna in the works just yet, but astronomers are beginning to plan for the possibility, and the ideal launch date for ...
[35]
Is Humanity Ignoring Our First Chance For A Mission To An Oort ...
May 22, 2018 · If we chose the 2033 launch, that would correspond to an arrival in late 2057, when Sedna will be 77.27 A.U. from the Sun. The 2046 window would ...
[36]
New Propulsion Systems Could Enable a Mission to Sedna
Jun 26, 2025 · An orbital mission would allow for extended study of Sedna, mapping its surface, analysing its composition, and potentially discovering moons ...
[37]
Feasibility study of a mission to Sedna -- Nuclear propulsion and ...
Jun 21, 2025 · This study assesses the feasibility of a mission to Sedna using two advanced propulsion concepts: the Direct Fusion Drive (DFD) rocket engine.Missing: ESA | Show results with:ESA
[38]
Direct Fusion Drive Could Take Us To Sedna During Its ... - IFLScience
Jun 30, 2025 · A team of researchers has outlined how a new "direct fusion drive" propulsion system could allow us to reach Sedna this century.<|control11|><|separator|>
[39]
Analysis of mission opportunities to Sedna in 2029–2034
Oct 1, 2021 · The article focuses on trajectory design to the trans-Neptunian object (90377) Sedna for launch in 2029–2034.Missing: facts | Show results with:facts